1. Field of the Invention
This invention relates to a security system and method for detecting counterfeit currency wherein security data encoded on articles of currency is compared with pre-stored security data in order to authenticate the currency during commercial transactions. If the comparison is true, the security data is dynamically updated and the currency is validated. If the comparison is false, the security data is invalidated and the currency is rejected.
2. Description of the Prior Art
The production of counterfeit currency is a problem that has grown dramatically in recent years. This increase is attributable, in large part, to the advent of color photocopy machines in the early 1990s, and the subsequent introduction of low cost color ink jet printers around 1994-1995. In 1997 alone, it is estimated that at least $30 million in counterfeit money was passed domestically, and this figure is expected to grow in the years ahead.
Existing technologies developed to address the counterfeiting problem include complicated embossing and microprinting techniques, and the use of optical scanners capable of detecting minute variances in currency features, such as printing pattern, color and sheet stock material. The principal deficiency of these existing anti-counterfeiting measures is that they rely on a person or device to identify variations between the features of a counterfeit bill and those of an authentic bill. Whether or not such comparisons are successful depends upon the sophistication of the counterfeiter and the capabilities of the counterfeit detection system. If the counterfeiter is able to reproduce a currency bill within some range of authenticity deemed acceptable by the detection equipment, the bill will go undetected and the counterfeiter will prevail. The result is that the government must develop more sophisticated detection equipment, which is inevitably followed by upgrades in the counterfeiter's methods and techniques. The problem of detection is thus never fully solved, and new detection devices with greater sensitivity must continually be sought.
It will be appreciated in light of the foregoing that there is a need in the art for a counterfeit currency detection system that does not rely on the feature detection schemes of the past. What is required is a new approach that implements a different and greatly improved technique for currency validation.